CHAPTER 23 THE EVOLUTIONS OF POPULATIONS. Section C: Genetic Variation, the Substrate for Natural Selection
|
|
- Kelly Fox
- 6 years ago
- Views:
Transcription
1 CHAPTER 23 THE EVOLUTIONS OF POPULATIONS Section C: Genetic Variation, the Substrate for Natural Selection 1. Genetic variation occurs within and between populations 2. Mutation and sexual recombination generate genetic variation 3. Diploidy and balanced polymorphisms preserve variation
2 1. Genetic variation occurs within and between populations The variation among individuals in a population is a combination of inheritable and non-heritable traits. Phenotype, the observable characteristics of an organism, is the cumulative product of an inherited genotype and a multitude of environmental influences. For example, these butterflies are genetically identical at the loci for coloration, but they emerge at different seasons. Fig. 23.7
3 Only the genetic component of variation can have evolutionary consequences as a result of natural selection. This is because only inheritable traits pass from generation to generation.
4 Both quantitative and discrete characters contribute to variation within a population. Quantitative characters are those that vary along a continuum within a population. For example, plant height in our wildflower population includes short and tall plants and everything in between. Quantitative variation is usually due to polygenic inheritance in which the additive effects of two or more genes influence a single phenotypic character. Discrete characters, such as flower color, are usually determined by a single locus with different alleles with distinct impacts on the phenotype.
5 Polymorphism occurs when two or more discrete characters are present and noticeable in a population. The contrasting forms are called morphs, as in the redflowered and white-flowered morphs in our wildflower population or the butterflies in the previous slide. Human populations are polymorphic for a variety of physical (e.g., freckles) and biochemical (e.g., blood types) characters. Polymorphism applies only to discrete characters, not quantitative characters, such as human height, which varies among people in a continuum.
6 Population geneticists measure genetic variation both at the level of whole genes and at the molecular level of DNA. Gene diversity measures the average percent of gene loci that are heterozygous. In the fruit fly (Drosophila), about 86% of their 13,000 gene loci are homozygous (fixed). About 14% (1,800 genes) are heterozygous.
7 Nucleotide diversity measures the level of difference in nucleotide sequences (base pair differences) among individuals in a population. In fruit flies, about 1% of the bases are different between two individuals. Two individuals would differ at 1.8 million of the 180 million nucleotides in the fruit fly genome. Humans have relatively little genetic variation. Gene diversity is about 14% in humans. Nucleotide diversity is only 0.1%. You and your neighbor have the same nucleotide at 999 out of every 1,000 nucleotide sites in your DNA.
8 Geographic variation results from differences in genetic structure either between populations or between subgroups of a single population that inhabit different areas. Often geographic variation results from natural selection that modifies gene frequencies in response to differences in local environmental factors. Alternatively, genetic drift can lead to chance variations among populations. Geographic variation can occur on a local scale, within a population, if the environment is patchy or if dispersal of individuals is limited, producing subpopulations.
9 Geographic variation in the form of graded change in a trait along a geographic axis is called a cline. Clines may represent intergrade zones where individuals from neighboring, genetically different, populations interbreed. Alternatively, clines may reflect the influence of natural selection on gradation in some environmental variable. For example, the average body size of many North American species of birds and mammals increases gradually with increasing latitude, perhaps conserving heat by decreasing the ratio of surface area to volume.
10 Clines may reflect direct environmental effects on phenotype, but also genetic differences along the cline. For example, average size of yarrow plants (Anchillea), gradually decreases with increasing variation. Although the environment affects growth rate directly to some extent with altitude, common garden experiments have demonstrated that some of the variation has a genetic basis. Fig. 23.8
11 In contrast to clines, isolated populations typically demonstrate discrete differences. For example, populations of house mice were first introduced to the island of Madiera in the 15th century, but isolated populations developed that were separated by mountains. Some isolated populations have evolved differences in karyotypes probably through genetic drift. Fig. 23.9
12 2. Mutation and sexual recombination generate genetic variation New alleles originate only by mutation. Mutations are changes in the nucleotide sequence of DNA. Mutations of individual genes are rare and random. Mutations in somatic cells are lost when the individual dies. Only mutations in cell lines that produce gametes can be passed along to offspring.
13 Most point mutations, those affecting a single base of DNA, are probably harmless. Most eukaryotic DNA does not code for proteins and mutations in these areas are likely to have little impact on phenotype. Even mutations in genes that code for proteins may lead to little effect because of redundancy in the genetic code. However, some single point mutations can have a significant impact on phenotype. Sickle-cell disease is caused by a single point mutation.
14 Mutations that alter the structure of a protein enough to impact its function are more likely to be harmful than beneficial. A random change is unlikely to improve a genome that is the product of thousands of generations of selection. Rarely, a mutant allele may enable an organism to fit its environment better and increase reproductive success. This is especially likely if the environment is changing These mutations may be beneficial now. For example, mutations that enable HIV to resist antiviral drugs are selected against under normal conditions, but are favorable under drug treatment.
15 Chromosomal mutations, including rearrangements of chromosomes, affect many genes and are likely to disrupt proper development of an organism. However, occasionally, these dislocations link genes together such that the phenotype is improved. Duplications of chromosome segments, whole chromosomes, or sets of chromosomes are nearly always harmful. However, when they are not harmful, the duplicates provide an expanded genome. These extra genes can now mutate to take on new functions.
16 Because microorganisms have very short generation times, mutation generates genetic variation rapidly. In an AIDS patient, HIV generates new viruses per day. With its RNA genome, mutation rate is higher than DNA genomes. This combination of mutation and replication rate will generate mutations in the HIV population at every site in the HIV genome every day. In the face of this high mutation rate, single-drug treatments are unlikely to be effective for very long and the most effective treatments are multiple drug cocktails. It is far less probable that mutations against all the drugs will appear in individual viruses in a short time.
17 In organisms with sexual reproduction, most of the genetic differences among individuals are due to unique recombinations of the existing alleles from the population gene pool. The ultimate origin of allelic variation is past mutations. Random segregation of homologous chromosomes and random union of gametes creates a unique assortment of alleles in each individual. Sexual reproduction recombines old alleles into fresh assortments every generation.
18 3. Diploidy and balanced polymorphism preserve variation The tendency for natural selection to reduce variation is countered by mechanisms that preserve or restore variation, including diploidy and balanced polymorphisms. Diploidy in eukaryotes prevents the elimination of recessive alleles via selection because they do not impact the phenotype in heterozygotes. Even recessive alleles that are unfavorable can persist in a population through their propagation by heterozygous individuals.
19 Recessive alleles are only exposed to selection when two parents carry the same recessive allele and these are combined in one zygote. This happens only rarely when the frequency of the recessive allele is very low. Heterozygote protection maintains a huge pool of alleles that may not be suitable under the present conditions but that could be beneficial when the environment changes.
20 Balanced polymorphism maintains genetic diversity in a population via natural selection. One mechanism in balance polymorphism is heterozygote advantage. In some situations individuals that are heterozygous at a particular locus have greater survivorship and reproductive success than homozygotes. In these cases, multiple alleles will be maintained at that locus by natural selection.
21 Heterozygous advantage maintains genetic diversity at the human locus for one chain of hemoglobin. A recessive allele causes sickle-cell disease in homozygous individuals. Homozygous dominant individuals are very vulnerable to malaria. Heterozygous individuals are resistant to malaria.
22 The frequency of the sickle-cell allele is highest in areas where the malarial parasite is common. The advantages of heterozygotes over homozygous recessive individuals who suffer sickle-cell disease and homozygous dominant individuals who suffer malaria are greatest here. The sickle-cell allele may reach 20% of the gene pool, with 32% heterozygotes resistant to malaria and 4% with sickle-cell disease. Fig
23 A second mechanism promoting balanced polymorphisms is frequency-dependent selection. Frequency-dependent selection occurs when the reproductive success of any one morph declines if that phenotype becomes too common in the population. The relationships between parasites and their hosts often demonstrate this type of relationship.
24 Hosts often vary in their defense against parasites and parasites in their ability to infect hosts. Those parasites that are capable of infecting the most common host type will increase in abundance. The rarer host types will increase as the genetic frequencies in the parasite population shifts. These shifts in genetic frequencies among hosts and among parasites maintain variation in both populations.
25 Aspects of this teeter-totter of frequency-dependent selection can be seen in the host-parasite between clones of aquatic snails and a parasitic worm. In these snails which reproduce asexually, the most common snail clones suffer the higher infection rates than the least common clone, suggesting frequencydependent selection. Fig
26 Some genetic variations, neutral variation, have negligible impact on reproductive success. For example, the diversity of human fingerprints seems to confer no selective advantage to some individuals over others. Much of the protein and DNA variation detectable by methods like electrophoresis may be neutral in their adaptive qualities. The relative frequencies of neural variations will not be affected by natural selection. Some neutral alleles will increase and others will decrease by the chance effects of genetic drift.
27 There is no consensus on how much genetic variation can be classified as neutral or even if any variation can be considered truly neutral. It is almost impossible to demonstrate that an allele brings no benefit at all to an organism. Also, variation may be neutral in one environment but not in another. Even if only a fraction of the extensive variation in a gene pool significantly affects an organism, there is still an enormous reservoir of raw material for natural selection and adaptive evolution.
Mechanisms of Evolution Microevolution. Key Concepts. Population Genetics
Mechanisms of Evolution Microevolution Population Genetics Key Concepts 23.1: Population genetics provides a foundation for studying evolution 23.2: Mutation and sexual recombination produce the variation
More informationNatural Selection. Population Dynamics. The Origins of Genetic Variation. The Origins of Genetic Variation. Intergenerational Mutation Rate
Natural Selection Population Dynamics Humans, Sickle-cell Disease, and Malaria How does a population of humans become resistant to malaria? Overproduction Environmental pressure/competition Pre-existing
More informationLife Cycles, Meiosis and Genetic Variability24/02/2015 2:26 PM
Life Cycles, Meiosis and Genetic Variability iclicker: 1. A chromosome just before mitosis contains two double stranded DNA molecules. 2. This replicated chromosome contains DNA from only one of your parents
More informationThe Evolution of Populations. Lecture Outline
Chapter 23 The Evolution of Populations Lecture Outline Overview: The Smallest Unit of Evolution One common misconception about evolution is that organisms evolve, in a Darwinian sense, during their lifetimes.
More informationSolutions to Problem Set 4
Question 1 Solutions to 7.014 Problem Set 4 Because you have not read much scientific literature, you decide to study the genetics of garden peas. You have two pure breeding pea strains. One that is tall
More informationQ Expected Coverage Achievement Merit Excellence. Punnett square completed with correct gametes and F2.
NCEA Level 2 Biology (91157) 2018 page 1 of 6 Assessment Schedule 2018 Biology: Demonstrate understanding of genetic variation and change (91157) Evidence Q Expected Coverage Achievement Merit Excellence
More informationProcesses of Evolution
15 Processes of Evolution Forces of Evolution Concept 15.4 Selection Can Be Stabilizing, Directional, or Disruptive Natural selection can act on quantitative traits in three ways: Stabilizing selection
More information(Write your name on every page. One point will be deducted for every page without your name!)
POPULATION GENETICS AND MICROEVOLUTIONARY THEORY FINAL EXAMINATION (Write your name on every page. One point will be deducted for every page without your name!) 1. Briefly define (5 points each): a) Average
More informationMajor questions of evolutionary genetics. Experimental tools of evolutionary genetics. Theoretical population genetics.
Evolutionary Genetics (for Encyclopedia of Biodiversity) Sergey Gavrilets Departments of Ecology and Evolutionary Biology and Mathematics, University of Tennessee, Knoxville, TN 37996-6 USA Evolutionary
More informationgenome a specific characteristic that varies from one individual to another gene the passing of traits from one generation to the next
genetics the study of heredity heredity sequence of DNA that codes for a protein and thus determines a trait genome a specific characteristic that varies from one individual to another gene trait the passing
More informationGenetical theory of natural selection
Reminders Genetical theory of natural selection Chapter 12 Natural selection evolution Natural selection evolution by natural selection Natural selection can have no effect unless phenotypes differ in
More informationReproduction and Evolution Practice Exam
Reproduction and Evolution Practice Exam Topics: Genetic concepts from the lecture notes including; o Mitosis and Meiosis, Homologous Chromosomes, Haploid vs Diploid cells Reproductive Strategies Heaviest
More informationMEIOSIS C H A P T E R 1 3
MEIOSIS CHAPTER 13 CENTRAL DOGMA OF BIOLOGY DNA RNA Protein OFFSPRING ACQUIRE GENES FROM PARENTS Genes are segments of DNA that program specific traits. Genetic info is transmitted as specific sequences
More informationObserving Patterns in Inherited Traits
Observing Patterns in Inherited Traits Chapter 10 Before you go on Review the answers to the following questions to test your understanding of previous material. 1. Most organisms are diploid. What does
More informationList the five conditions that can disturb genetic equilibrium in a population.(10)
List the five conditions that can disturb genetic equilibrium in a population.(10) The five conditions are non-random mating, small population size, immigration or emigration, mutations, and natural selection.
More informationChapter 13 Meiosis and Sexual Reproduction
Biology 110 Sec. 11 J. Greg Doheny Chapter 13 Meiosis and Sexual Reproduction Quiz Questions: 1. What word do you use to describe a chromosome or gene allele that we inherit from our Mother? From our Father?
More informationFull file at CHAPTER 2 Genetics
CHAPTER 2 Genetics MULTIPLE CHOICE 1. Chromosomes are a. small linear bodies. b. contained in cells. c. replicated during cell division. 2. A cross between true-breeding plants bearing yellow seeds produces
More informationMutation, Selection, Gene Flow, Genetic Drift, and Nonrandom Mating Results in Evolution
Mutation, Selection, Gene Flow, Genetic Drift, and Nonrandom Mating Results in Evolution 15.2 Intro In biology, evolution refers specifically to changes in the genetic makeup of populations over time.
More informationScience Unit Learning Summary
Learning Summary Inheritance, variation and evolution Content Sexual and asexual reproduction. Meiosis leads to non-identical cells being formed while mitosis leads to identical cells being formed. In
More informationSince we re not going to have review this week either
Since we re not going to have review this week either I am posting these slides to help with reviewing the material that we didn t cover during discussion sessions these past two weeks. Of course, take
More informationEvolution of Populations. Chapter 17
Evolution of Populations Chapter 17 17.1 Genes and Variation i. Introduction: Remember from previous units. Genes- Units of Heredity Variation- Genetic differences among individuals in a population. New
More informationUnit 4 Review - Genetics. UNIT 4 Vocabulary topics: Cell Reproduction, Cell Cycle, Cell Division, Genetics
Unit 4 Review - Genetics Sexual vs. Asexual Reproduction Mendel s Laws of Heredity Patterns of Inheritance Meiosis and Genetic Variation Non-Mendelian Patterns of Inheritance Cell Reproduction/Cell Cycle/
More informationNatural Selection results in increase in one (or more) genotypes relative to other genotypes.
Natural Selection results in increase in one (or more) genotypes relative to other genotypes. Fitness - The fitness of a genotype is the average per capita lifetime contribution of individuals of that
More informationname: Worksheets for Ch 14, 15, 16 Evolution
name: Worksheets for Ch 14, 15, 16 Evolution Classify the following scenarios as examples of either artificial or natural selection by placing the letter for each scenario into the appropriate box below.
More informationThe theory of evolution continues to be refined as scientists learn new information.
Section 3: The theory of evolution continues to be refined as scientists learn new information. K What I Know W What I Want to Find Out L What I Learned Essential Questions What are the conditions of the
More informationUnit 3 - Molecular Biology & Genetics - Review Packet
Name Date Hour Unit 3 - Molecular Biology & Genetics - Review Packet True / False Questions - Indicate True or False for the following statements. 1. Eye color, hair color and the shape of your ears can
More informationGuided Notes Unit 6: Classical Genetics
Name: Date: Block: Chapter 6: Meiosis and Mendel I. Concept 6.1: Chromosomes and Meiosis Guided Notes Unit 6: Classical Genetics a. Meiosis: i. (In animals, meiosis occurs in the sex organs the testes
More informationEvolution by Natural Selection
Evolution by Natural Selection What is evolution? What is evolution? The change in the genetic makeup of a population over time (narrowly defined) Evolution accounts for the diversity of life on Earth
More information6.6 Meiosis and Genetic Variation. KEY CONCEPT Independent assortment and crossing over during meiosis result in genetic diversity.
6.6 Meiosis and Genetic Variation KEY CONCEPT Independent assortment and crossing over during meiosis result in genetic diversity. 6.6 Meiosis and Genetic Variation! Sexual reproduction creates unique
More information1 Errors in mitosis and meiosis can result in chromosomal abnormalities.
Slide 1 / 21 1 Errors in mitosis and meiosis can result in chromosomal abnormalities. a. Identify and describe a common chromosomal mutation. Slide 2 / 21 Errors in mitosis and meiosis can result in chromosomal
More informationNOTES CH 17 Evolution of. Populations
NOTES CH 17 Evolution of Vocabulary Fitness Genetic Drift Punctuated Equilibrium Gene flow Adaptive radiation Divergent evolution Convergent evolution Gradualism Populations 17.1 Genes & Variation Darwin
More informationReview sheet for Mendelian genetics through human evolution. What organism did Mendel study? What characteristics of this organism did he examine?
Review sheet for Mendelian genetics through human evolution WARNING: I have tried to be complete, but I may have missed something. You are responsible for all the material discussed in class. This is only
More informationEVOLUTION ALGEBRA Hartl-Clark and Ayala-Kiger
EVOLUTION ALGEBRA Hartl-Clark and Ayala-Kiger Freshman Seminar University of California, Irvine Bernard Russo University of California, Irvine Winter 2015 Bernard Russo (UCI) EVOLUTION ALGEBRA 1 / 10 Hartl
More informationStudy of similarities and differences in body plans of major groups Puzzling patterns:
Processes of Evolution Evolutionary Theories Widely used to interpret the past and present, and even to predict the future Reveal connections between the geological record, fossil record, and organismal
More informationUNIT 8 BIOLOGY: Meiosis and Heredity Page 148
UNIT 8 BIOLOGY: Meiosis and Heredity Page 148 CP: CHAPTER 6, Sections 1-6; CHAPTER 7, Sections 1-4; HN: CHAPTER 11, Section 1-5 Standard B-4: The student will demonstrate an understanding of the molecular
More informationLesson 2 Evolution of population (microevolution)
Lesson 2 Evolution of population (microevolution) 1. A gene pool consists of a. all the aleles exposed to natural selection. b. the total of all alleles present in a population. c. the entire genome of
More informationPerplexing Observations. Today: Thinking About Darwinian Evolution. We owe much of our understanding of EVOLUTION to CHARLES DARWIN.
Today: Thinking About Darwinian Evolution Part 1: Darwin s Theory Perplexing Observations Mystery of the Black Death?? What is evolution?? And what is this finch doing?!? We owe much of our understanding
More informationAP Biology Evolution Review Slides
AP Biology Evolution Review Slides How would one go about studying the evolution of a tetrapod limb from a fish s fin? Compare limb/fin structure of existing related species of fish to tetrapods Figure
More informationUnit 6 Reading Guide: PART I Biology Part I Due: Monday/Tuesday, February 5 th /6 th
Name: Date: Block: Chapter 6 Meiosis and Mendel Section 6.1 Chromosomes and Meiosis 1. How do gametes differ from somatic cells? Unit 6 Reading Guide: PART I Biology Part I Due: Monday/Tuesday, February
More informationName: Period: EOC Review Part F Outline
Name: Period: EOC Review Part F Outline Mitosis and Meiosis SC.912.L.16.17 Compare and contrast mitosis and meiosis and relate to the processes of sexual and asexual reproduction and their consequences
More informationMeiosis and Sexual Life Cycles
Chapter 13 Meiosis and Sexual Life Cycles Lecture Outline Overview: Variations on a Theme Living organisms are distinguished by their ability to reproduce their own kind. Offspring resemble their parents
More informationGenetics (patterns of inheritance)
MENDELIAN GENETICS branch of biology that studies how genetic characteristics are inherited MENDELIAN GENETICS Gregory Mendel, an Augustinian monk (1822-1884), was the first who systematically studied
More informationBIOLOGY FINAL EXAM REVIEW SHEET Chapters 10-15, 17-30
Name Hour Due Date: BIOLOGY FINAL EXAM REVIEW SHEET Chapters 10-15, 17-30 The exam was prepared by the Biology teachers in the science departments of CVHS and DHS. 1. What is a Punnett Square? 2. Cross
More informationBiological Change Over Time. Lecture 12: Evolution. Microevolution. Microevolutionary Processes. Genotypes, Phenotypes and Environmental Effects
Lecture 12: Evolution Biological Change Over Time Key terms: Reading: Ch16: Microevolution Ch17:Speciation Ch18:Macroevolution Microevolution Changes with in species Well defined mechanism Easily observed
More informationUNIT V. Chapter 11 Evolution of Populations. Pre-AP Biology
UNIT V Chapter 11 Evolution of Populations UNIT 4: EVOLUTION Chapter 11: The Evolution of Populations I. Genetic Variation Within Populations (11.1) A. Genetic variation in a population increases the chance
More informationBiology Semester 2 Final Review
Name Period Due Date: 50 HW Points Biology Semester 2 Final Review LT 15 (Proteins and Traits) Proteins express inherited traits and carry out most cell functions. 1. Give examples of structural and functional
More informationEvolution - Unifying Theme of Biology Microevolution Chapters 13 &14
Evolution - Unifying Theme of Biology Microevolution Chapters 13 &14 New Synthesis Natural Selection Unequal Reproductive Success Examples and Selective Forces Types of Natural Selection Speciation http://www.biology-online.org/2/11_natural_selection.htm
More informationObjective 3.01 (DNA, RNA and Protein Synthesis)
Objective 3.01 (DNA, RNA and Protein Synthesis) DNA Structure o Discovered by Watson and Crick o Double-stranded o Shape is a double helix (twisted ladder) o Made of chains of nucleotides: o Has four types
More informationEvolution in Populations Worksheets
Evolution in Populations Worksheets CK12 Editor Say Thanks to the Authors Click http://www.ck12.org/saythanks (No sign in required) To access a customizable version of this book, as well as other interactive
More informationCell Division: the process of copying and dividing entire cells The cell grows, prepares for division, and then divides to form new daughter cells.
Mitosis & Meiosis SC.912.L.16.17 Compare and contrast mitosis and meiosis and relate to the processes of sexual and asexual reproduction and their consequences for genetic variation. 1. Students will describe
More informationEvolution & Natural Selection
Evolution & Natural Selection Learning Objectives Know what biological evolution is and understand the driving force behind biological evolution. know the major mechanisms that change allele frequencies
More informationThis is DUE: Come prepared to share your findings with your group.
Biology 160 NAME: Reading Guide 11: Population Dynamics, Humans, Part I This is DUE: Come prepared to share your findings with your group. *As before, please turn in only the Critical Thinking questions
More informationTHE WORK OF GREGOR MENDEL
GENETICS NOTES THE WORK OF GREGOR MENDEL Genetics-. - Austrian monk- the father of genetics- carried out his work on. Pea flowers are naturally, which means that sperm cells fertilize the egg cells in
More informationMeiosis and Mendel. Chapter 6
Meiosis and Mendel Chapter 6 6.1 CHROMOSOMES AND MEIOSIS Key Concept Gametes have half the number of chromosomes that body cells have. Body Cells vs. Gametes You have body cells and gametes body cells
More informationThere are 3 parts to this exam. Use your time efficiently and be sure to put your name on the top of each page.
EVOLUTIONARY BIOLOGY EXAM #1 Fall 2017 There are 3 parts to this exam. Use your time efficiently and be sure to put your name on the top of each page. Part I. True (T) or False (F) (2 points each). Circle
More informatione.g. population: 500, two alleles: Red (R) and White (r). Total: 1000 genes for flower color in the population
The Evolution of Populations What is Evolution? A change over time in the genetic composition of a population Human evolution The gene pool Is the total aggregate of genes for a particular trait in a population
More informationoverproduction variation adaptation Natural Selection speciation adaptation Natural Selection speciation
Evolution Evolution Chapters 22-25 Changes in populations, species, or groups of species. Variances of the frequency of heritable traits that appear from one generation to the next. 2 Areas of Evolutionary
More informationDNA Structure and Function
DNA Structure and Function Nucleotide Structure 1. 5-C sugar RNA ribose DNA deoxyribose 2. Nitrogenous Base N attaches to 1 C of sugar Double or single ring Four Bases Adenine, Guanine, Thymine, Cytosine
More information1. The diagram below shows two processes (A and B) involved in sexual reproduction in plants and animals.
1. The diagram below shows two processes (A and B) involved in sexual reproduction in plants and animals. Which statement best explains how these processes often produce offspring that have traits not
More informationName Period. 2. Name the 3 parts of interphase AND briefly explain what happens in each:
Name Period GENERAL BIOLOGY Second Semester Study Guide Chapters 3, 4, 5, 6, 11, 10, 13, 14, 15, 16, and 17. SEXUAL REPRODUCTION AND MEIOSIS 1. The cell cycle consists of a growth stage and a division
More informationGene Pool The combined genetic material for all the members of a population. (all the genes in a population)
POPULATION GENETICS NOTES Gene Pool The combined genetic material for all the members of a population. (all the genes in a population) Allele Frequency The number of times a specific allele occurs in a
More informationHEREDITY AND VARIATION
HEREDITY AND VARIATION OVERVIEW Students often do not understand the critical role of variation to evolutionary processes. In fact, variation is the only fundamental requirement for evolution to occur.
More informationEOC - Unit 4 Review - Genetics
EOC - Unit 4 Review - Genetics Part A: Benchmark Standard SC.912.L.16.1 Use Mendel s laws of segregation and independent assortment to analyze patterns of inheritance. Also Assesses SC.912.L.16.2 Discuss
More informationChapter 6 Meiosis and Mendel
UNIT 3 GENETICS Chapter 6 Meiosis and Mendel 1 hairy ears (hypertrichosis)- due to holandric gene. (Y chromosome)-only occurs in males. Appears in all sons. 2 Polydactyly- having extra fingers Wendy the
More informationChromosome duplication and distribution during cell division
CELL DIVISION AND HEREDITY Student Packet SUMMARY IN EUKARYOTES, HERITABLE INFORMATION IS PASSED TO THE NEXT GENERATION VIA PROCESSES THAT INCLUDE THE CELL CYCLE, MITOSIS /MEIOSIS AND FERTILIZATION Mitosis
More informationUntitled Document. A. antibiotics B. cell structure C. DNA structure D. sterile procedures
Name: Date: 1. The discovery of which of the following has most directly led to advances in the identification of suspects in criminal investigations and in the identification of genetic diseases? A. antibiotics
More informationDesigner Genes C Test
Northern Regional: January 19 th, 2019 Designer Genes C Test Name(s): Team Name: School Name: Team Number: Rank: Score: Directions: You will have 50 minutes to complete the test. You may not write on the
More informationChapter 4 Lesson 1 Heredity Notes
Chapter 4 Lesson 1 Heredity Notes Phases of Meiosis I Prophase I Nuclear membrane breaks apart and chromosomes condense. 3.1 Sexual Reproduction and Meiosis Metaphase I Sister chromatids line up along
More informationTexas Biology Standards Review. Houghton Mifflin Harcourt Publishing Company 26 A T
2.B.6. 1 Which of the following statements best describes the structure of DN? wo strands of proteins are held together by sugar molecules, nitrogen bases, and phosphate groups. B wo strands composed of
More informationREVIEW 6: EVOLUTION. 1. Define evolution: Was not the first to think of evolution, but he did figure out how it works (mostly).
Name: REVIEW 6: EVOLUTION 1. Define evolution: 2. Modern Theory of Evolution: a. Charles Darwin: Was not the first to think of evolution, but he did figure out how it works (mostly). However, Darwin didn
More informationEvolution. Before You Read. Read to Learn
Evolution 15 section 3 Shaping Evolutionary Theory Biology/Life Sciences 7.e Students know the conditions for Hardy-Weinberg equilibrium in a population and why these conditions are not likely to appear
More informationName Period. 3. How many rounds of DNA replication and cell division occur during meiosis?
Name Period GENERAL BIOLOGY Second Semester Study Guide Chapters 3, 4, 5, 6, 11, 14, 16, 17, 18 and 19. SEXUAL REPRODUCTION AND MEIOSIS 1. What is the purpose of meiosis? 2. Distinguish between diploid
More information- mutations can occur at different levels from single nucleotide positions in DNA to entire genomes.
February 8, 2005 Bio 107/207 Winter 2005 Lecture 11 Mutation and transposable elements - the term mutation has an interesting history. - as far back as the 17th century, it was used to describe any drastic
More information1. A segment of a DNA strand has the following bases:
North arolina Testing Program EO iology Sample Items Goal 3 1. segment of a N strand has the following bases: T GT 4. efore a cell goes through either mitosis or meiosis, which process must be carried
More informationMicroevolution (Ch 16) Test Bank
Microevolution (Ch 16) Test Bank Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Which of the following statements describes what all members
More informationBiology Final Review Ch pg Biology is the study of
Biology Final Review Ch. 1 1-3 pg. 17-25 1. Biology is the study of Ch.2 2-3 pg. 45-49 2. All organic compounds contain. 3. Starch is an example of which type of organic compound? 4. What monomers make
More information1. Draw, label and describe the structure of DNA and RNA including bonding mechanisms.
Practicing Biology BIG IDEA 3.A 1. Draw, label and describe the structure of DNA and RNA including bonding mechanisms. 2. Using at least 2 well-known experiments, describe which features of DNA and RNA
More informationPopulation Genetics & Evolution
The Theory of Evolution Mechanisms of Evolution Notes Pt. 4 Population Genetics & Evolution IMPORTANT TO REMEMBER: Populations, not individuals, evolve. Population = a group of individuals of the same
More informationHeredity Variation Genetics Meiosis
Genetics Warm Up Exercise: -Using your previous knowledge of genetics, determine what maternal genotype would most likely yield offspring with such characteristics. -Use the genotype that you came up with
More informationName Class Date. KEY CONCEPT Gametes have half the number of chromosomes that body cells have.
Section 1: Chromosomes and Meiosis KEY CONCEPT Gametes have half the number of chromosomes that body cells have. VOCABULARY somatic cell autosome fertilization gamete sex chromosome diploid homologous
More informationDarwinian Selection. Chapter 7 Selection I 12/5/14. v evolution vs. natural selection? v evolution. v natural selection
Chapter 7 Selection I Selection in Haploids Selection in Diploids Mutation-Selection Balance Darwinian Selection v evolution vs. natural selection? v evolution ² descent with modification ² change in allele
More informationLecture #4-1/25/02 Dr. Kopeny
Lecture #4-1/25/02 Dr. Kopeny Genetic Drift Can Cause Evolution Genetic Drift: Random change in genetic structure of a population; due to chance Thought Experiment: What is your expectation regarding the
More informationQuantitative Genetics & Evolutionary Genetics
Quantitative Genetics & Evolutionary Genetics (CHAPTER 24 & 26- Brooker Text) May 14, 2007 BIO 184 Dr. Tom Peavy Quantitative genetics (the study of traits that can be described numerically) is important
More informationEnduring Understanding: Change in the genetic makeup of a population over time is evolution Pearson Education, Inc.
Enduring Understanding: Change in the genetic makeup of a population over time is evolution. Objective: You will be able to identify the key concepts of evolution theory Do Now: Read the enduring understanding
More informationThe Mechanisms of Evolution
The Mechanisms of Evolution Figure.1 Darwin and the Voyage of the Beagle (Part 1) 2/8/2006 Dr. Michod Intro Biology 182 (PP 3) 4 The Mechanisms of Evolution Charles Darwin s Theory of Evolution Genetic
More informationCh 11.Introduction to Genetics.Biology.Landis
Nom Section 11 1 The Work of Gregor Mendel (pages 263 266) This section describes how Gregor Mendel studied the inheritance of traits in garden peas and what his conclusions were. Introduction (page 263)
More informationBIOLOGY LTF DIAGNOSTIC TEST MEIOSIS & MENDELIAN GENETICS
016064 BIOLOGY LTF DIAGNOSTIC TEST MEIOSIS & MENDELIAN GENETICS TEST CODE: 016064 Directions: Each of the questions or incomplete statements below is followed by five suggested answers or completions.
More informationGene Pool Genetic Drift Geographic Isolation Fitness Hardy-Weinberg Equilibrium Natural Selection
CONCEPT 1 EVOLUTION 1. Natural Selection a. Major mechanism of change over time Darwin s theory of evolution b. There is variation among phenotypes genetic mutations play a role in increasing variation
More informationVariation of Traits. genetic variation: the measure of the differences among individuals within a population
Genetic variability is the measure of the differences among individuals within a population. Because some traits are more suited to certain environments, creating particular niches and fits, we know that
More informationBig Idea #1: The process of evolution drives the diversity and unity of life
BIG IDEA! Big Idea #1: The process of evolution drives the diversity and unity of life Key Terms for this section: emigration phenotype adaptation evolution phylogenetic tree adaptive radiation fertility
More informationSexual Reproduction and Genetics
Chapter Test A CHAPTER 10 Sexual Reproduction and Genetics Part A: Multiple Choice In the space at the left, write the letter of the term, number, or phrase that best answers each question. 1. How many
More informationPlant Propagation PLS 3221/5222
Plant Propagation PLS 3221/5222 Dr. Sandra Wilson Dr. Mack Thetford Chapter 2 Introduction to the Biology of Plant Propagation -A review- 1 The Plant Breeder and the Plant Propagator Plant Breeder, The
More informationBiology. Revisiting Booklet. 6. Inheritance, Variation and Evolution. Name:
Biology 6. Inheritance, Variation and Evolution Revisiting Booklet Name: Reproduction Name the process by which body cells divide:... What kind of cells are produced this way? Name the process by which
More informationBiology. Chapter 12. Meiosis and Sexual Reproduction. Concepts and Applications 9e Starr Evers Starr. Cengage Learning 2015
Biology Concepts and Applications 9e Starr Evers Starr Chapter 12 Meiosis and Sexual Reproduction 12.1 Why Sex? In asexual reproduction, a single individual gives rise to offspring that are identical to
More informationThe Chromosomal Basis of Inheritance
The Chromosomal Basis of Inheritance Mitosis and meiosis were first described in the late 800s. The chromosome theory of inheritance states: Mendelian genes have specific loci (positions) on chromosomes.
More informationHeredity Composite. Multiple Choice Identify the choice that best completes the statement or answers the question.
Heredity Composite Multiple Choice Identify the choice that best completes the statement or answers the question. 1. When a plant breeder crossed two red roses, 78% of the offspring had red flowers and
More information9 Genetic diversity and adaptation Support. AQA Biology. Genetic diversity and adaptation. Specification reference. Learning objectives.
Genetic diversity and adaptation Specification reference 3.4.3 3.4.4 Learning objectives After completing this worksheet you should be able to: understand how meiosis produces haploid gametes know how
More information5/31/2012. Speciation and macroevolution - Chapter
Speciation and macroevolution - Chapter Objectives: - Review meiosis -Species -Repro. Isolating mechanisms - Speciation -Is evolution always slow -Extinction How Are Populations, Genes, And Evolution Related?
More informationSexual Reproduction and Genetics
Sexual Reproduction and Genetics Mitosis is a form of asexual reproduction This means that it only requires 1 organism (ex. Skin cells dividing) For growth and repair in somatic (body) cells! Results
More informationLearning Objectives LO 3.7 The student can make predictions about natural phenomena occurring during the cell cycle. [See SP 6.4]
Big Ideas 3.A.2: In eukaryotes, heritable information is passed to the next generation via processes that include the cell cycle and mitosis or meiosis plus fertilization. CHAPTER 13 MEIOSIS AND SEXUAL
More information